I have noticed over the years that most Boeing 707s and 720s had small galley service doors on front and rear.There are some exceptions.
American Airlines Boeing 707-123B and 720B had a front full size galley service door but the rear was the standard small door.Their 707-323B and Cs did not have full size service doors just the standard small size.
Eastern Airlines Boeing 720s had full size service doors at the front and rear inaddition Eastern's 720s had two overwing exits.
United's 720s had full size service doors at both ends.
Western's 720Bs had a front full size service door while the rear was the standard small door.
What other airlines had this?Was this an optional feature Boeing offered at the time? I never saw any of the 707-320 series have the large service doors,just the smaller doors.